Just like XBOX Live, you can be sure that users will have to pay to play online. Messaging will most likely be free like on XBOX Live. If developers build a game around XBOX Live for multiplayer, users will pay or they won't play. It's that simple. 100% incorrect.
For one, users are used to things being free on PCs. They aren't on consoles. So no one will bother buying the pay games on the PC.
For another, PC gamers have much more control over their systems. Microsoft can create a pay service if they like (they won't), PC gamers will find ways around it. They always have. Won and Steam haven't fully prevented people from playing the Half Life games in the way they see best.
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